Rational points on X 0 + (N) and quadratic ℚ-curves
Journal de théorie des nombres de Bordeaux, Tome 14 (2002) no. 1, pp. 205-219.

Nous considérons les points rationnels sur X 0 (N)/W N dans le cas où N est un nombre composé. Nous faisons une étude de certains cas qui ne se déduisent pas des résultats de Momose. Des points rationnels sont obtenus pour N=91 et N=125. Nous exhibons aussi les j-invariants des ℚ-courbes quadratiques correspondantes.

The rational points on X 0 (N)/W N in the case where N is a composite number are considered. A computational study of some of the cases not covered by the results of Momose is given. Exceptional rational points are found in the cases N=91 and N=125 and the j-invariants of the corresponding quadratic ℚ-curves are exhibited.

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Galbraith, Steven D. Rational points on $X_0^+ (N)$ and quadratic $\mathbb {Q}$-curves. Journal de théorie des nombres de Bordeaux, Tome 14 (2002) no. 1, pp. 205-219. http://www.numdam.org/item/JTNB_2002__14_1_205_0/

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